This review of the literature addresses scientific and methodological concerns of research with children from various racial and ethnic backgrounds in the United States. It first identifies three major demographic trends: (1) the increasingly multiethnic and multilingual nature of American society; (2) the increasing number of children in poverty; and (3) the increased risk of needing special education services when conditions of poverty and racial and language diversity exist. Specific challenges to researchers are discussed, including the relationship among race, ethnicity, socioeconomic status, and gender. The importance of epistemological considerations is also noted, especially considering issues of race categorization, ethics, and human values. Issues raised by the underlying assumptions of quantitative research methodology are noted, including sampling, instrumentation, and measurement. The importance of the mutual support of research and practice is stressed. (Contains 50 references.) (DB)